64 OUTLINES OF ANATOMY. 



The Mammary Glands 



Vessels and nerves : 



Arteries. Veins. Lymphatics. Nerves. 



Development. Abnormalities. Nipples. 



Dissect off the superficial fascia and expose the pectoral fascia, and deep fascia of the upper third of the 

 arm. 



Pectoral fascia, 308-9. (311) 



Deep fascia of arm, 321-2. (323-4) 



Reflect the deep fascia from the surface of the pectoralis major by dissecting parallel with the course 

 of its fibres. Expose also the anterior portion of the deltoid and remove the deep fascia from the 

 upper third of the front of the arm. 



Pectoralis major, 309-10-11 ; Fig. 264. (311-12-13) 



Origin. Insertion. Structure ; clavicular, sterno-costal portion. 

 Nerve-supply. Action. Relations. Variations. 



In the interval between the pectoralis major and deltoid, exposed by separating the contiguous 

 borders of the muscles, are the cephalic vein and the humeral branch of the acromio-thoracic artery. 



Cephalic vein, 680-1 ; Fig. 396. (666) 



Humeral branch of the acromio-thoracic artery, 555. (545) 



Carefully reflect the clavicular portion of the pectoralis major by detaching it from the clavicle and 

 turning it downward ; note the branches of the external anterior thoracic nerve entering its deep sur- 

 face. The clavi-pectoral fascia should be carefully exposed in the interval between the clavicle and 

 the pectoralis minor, and its connections and relations noted. 



Clavi-pectoral fascia, costo-coracoid membrane, 308. (311) 



Remove the costo-coracoid membrane and expose the subclavius muscle. Trace the cephalic vein to 

 its termination and expose that portion of the axillary vein between the clavicle and the upper border 

 of the pectoralis minor. Also, the first portion of the axillery artery and that part of the brachial 

 plexus in relation with the vessels. Note the thoracic branches of the brachial plexus crossing in front 

 of the vessels to the pectoral muscles. Demonstrate the thoracic axis and its branches and expose the 

 - origin of the superior thoracic artery. 



Sublcavius, 311-12-13; Fig, 265. (313-14) 



Origin. Insertion. Structure. Nerve-supply. Action. Relations. Variations. 

 Axillary vein, 682. (668) 

 The axillary artery, 552. (542) 



First part of the axillary artery : 



Relations : In front. Behind. Outer side. Inner side. 

 Branches of the first part of the axillary artery, 555. (543-5) 

 Acromio-thoracic or thoracic axis : 

 Acromial branch. 

 Pectoral branch. 

 Clavicular branch. 

 Superior or short thoracic. 

 External anterior thoracic nerve, 835. (815) 

 Internal anterior thoracic nerve, 835. (815) 



Turn off the superficial fascia of the axilla, exposing the deep fascia or axillary fascia. 

 Axillary fascia, 308-9. (311) 



Beginning at the anterior border of the axilla, separate the deep fascia from the lower border of the pec- 

 toralis major and carefully reflect it backward to the posterior border of the space. In the reflection 

 of the fascia care must be exercised not to injure the lateral cutaneous branches of the second and third 

 intercostal nerves. 



Intercosto-humeral nerve, 845 ; Fig. 460. (825) 



Lateral cutaneous branch of the third intercostal, 845. (825-6) 



Axillary glands, 695 ; Fig. 399. (679-80) 



Carefully dissect out the lymphatics, fat, and connective tissue, exposing the third portion of the axillary 

 artery and the divisions of the brachial plexus in relation with it. 



Third part of the axillary artery, 553. (543) 



Relations: In front. Behind. Outer side. Inner side. 



